Technical Field
The present invention relates to cages, communication devices, communication modules, and connecting methods.
Related Art
In the field of high-speed optical communication using optical fibers, pluggable optical transceivers that convert electrical signals with optical signals and vice versa are used. With the pluggable optical transceivers, a cage is installed on a main board in a communication device side (host side), an optical module (communication terminal) integrated with a photoelectric conversion element and a circuit board is inserted in the cage, and an optical module-side connector (module-side connector) and a main board-side connector (fixed-side connector) are connected electrically and mechanically. Thus, the optical signals to be transferred and received with the optical fibers and the electrical signals to be processed with the main board in the communication device side can be converted with each other with the photoelectric conversion element and the circuit board in the optical module.
In Japanese Patent Application Laid-open Publication No. 2013-134347, an optical module that is insertable to and removable from a cage is disclosed. The optical module disclosed in Japanese Patent Application Laid-open Publication No. 2013-134347 is integrated with a board shown in FIG. 14, and a card edge connector arranged with multiple connecting terminals in an end portion of the board is formed. In Japanese Patent Application Laid-open Publication No. 2012-163739, there is also disclosed a connector arranged with multiple connecting terminals in an end portion of the board.
As connectors different from the card edge connector, there are known connectors disclosed in WO2009/128413A1, WO2003/054608A1, and SNAP12 MSA Revision 1.1 May 15, 2002 (http://www.physik.unizh.ch/˜avollhar/snap12msa_051502.pdf). With these connectors, by arranging the connecting terminals (for example, the connecting pins) two-dimensionally, the connecting terminals can be arranged in high density, and the connecting terminals are appropriate for high-speed signal transmission. Note that, as the connectors with the connecting terminals arranged two-dimensionally, there are known, for example, MEG-Array (registered trademark).
In the case of the card edge connectors disclosed in Japanese Patent Application Laid-open Publication No. 2013-134347 and No. 2012-163739, the attachable/detachable direction of the connectors and the insertable/removable direction of the optical module match. Thus, by inserting the optical module adopting the card edge connector in the cage, the connector can be connected as is.
In the case of the card edge connectors disclosed in Japanese Patent Application Laid-open Publication No. 2013-134347 and No. 2012-163739 however, the connecting terminals are arranged aligned in only a width direction of a board of the optical module, thus the connecting terminals cannot be arranged in high-density and are not suited for higher speed signal transmission. Further, in the case of the card edge connector, wiring between the connecting terminals of the main board-side connector (fixed-side connector) and the main board becomes long, thus in this regard it is also not suited for high-speed signal transmission. For higher speed signal transmission, it is advantageous to adopt a connector with connecting terminals arranged two-dimensionally on a plane in parallel with a board, as the connectors disclosed in WO2009/128413A1 and WO2003/054608A1 and SNAP12 MSA Revision 1.1 May 15, 2002 (http://www.physik.unizh.ch/˜avollhar/snap12msa_051502.pdf).
As with the connectors disclosed in WO2009/128413A1 and WO2003/054608A1 and SNAP12 MSA Revision 1.1 May 15, 2002 (http://www.physik.unizh.ch/˜avollhar/snap12msa_051502.pdf), in the case of the connector with the connecting terminals arranged two-dimensionally, the connecting terminals are aligned in a surface in parallel with the board (the board of the optical module or a main board), thus the direction in which the connector is to be attached/detached is a direction that intersects with the board (for example, a direction perpendicular to the board). On the contrary, the optical module that is insertable to and removable from the cage is inserted or removed substantially in parallel with the board (the board of the optical module or the main board). In other words, even if the connector with the connecting terminals arranged two-dimensionally is adopted as the optical module (an optical module that is insertable/removable with respect to the cage), the attaching/detaching direction of the connector (a direction that intersects a connector surface with the connecting terminals arranged two-dimensionally) and an inserting/removing direction of the optical module do not match. In this way, the optical modules disclosed in WO2009/128413A1, WO2003/054608A1, and SNAP12 MSA Revision 1.1 May 15, 2002 (http://www.physik.unizh.ch/˜avollhar/snap12msa_051502.pdf) are fixed with respect to the board, and have not been considered at all regarding inserting/removing to/from with respect to the cage.
Note that, such a problem is not limited to the optical module, and is also a problem that exists in relation to other communication modules (communication terminals) such as an electric module.